Several types of power converters have been proposed in research literature based on the requirement of different applications. In state-of-the-art research, many examples of DC-DC converter are found for renewable energy system such as photovoltaic system, wind energy system, fuel cell powered system and so on. There are various ways to interface Photovoltaic (PV) modules with DC-AC inverter. Generally, the substrings of PV cells are connected in series in a PV module and the module is connected to the DC-DC converter before connecting to the DC-AC inverter since the low output voltage of PV module needs to be boosted to interface with the inverter. The output voltage of the substrings within a PV module varies from time to time inter alia due to the shading effect. This phenomenon also may affect the overall efficiency of the photovoltaic system in different operating conditions. Moreover, the generated current of the solar cells in a PV module can differ due to the shading effect in different parts of the module. These output power mismatch between the cells and/or substrings can cause significant power loss. In order to deal with the power mismatch problem at the module level distributed power management technique is presented in research literature. Although limited studies are available, some of the approaches in the literature deal with mismatch problems inside the module at the substring level. In order to overcome mismatch problem between substrings of the PV module an intra-module DC-DC converter for PV application has been presented by Chatterjee et al in 28th EU PVSEC, 2013, pp. 3419-3423. The design requirements and also the effectiveness of the designed converter as an intra-module converter have been discussed there.
In state of the art research, some of the literature focuses on the module level very high gain DC-DC converter to address the mismatch problem that decreases the impact of mismatches by performing MPPT (Maximum Power Point Tracking) at module level. Literature introduces several DC-DC converters of high dc-dc boost ratio multistage converter. In a previous attempt, high gain high power DC-DC boost converter is presented based on three state switching cell and voltage multiplier cell. Auto-transfer along with multiplier cells are used to achieve high voltage gain. A non-isolated three level hybrid boost converter is for instance proposed by Zhang et al, in IEEE Transactions on Power Electronics, Vol. 28, no. 8 (2013). No transformer or coupled inductor is used in this converter rather multiple power switches and diodes are used to achieve high gain.
The above mentioned converters are capable to achieve high voltage gain. However, wide input voltage range and wide voltage gain range are not addressed simultaneously.
There is always room for improvements or alternatives.